Ethers of resin alcohols and method for their production



Patented Sept. 28, 1937 ETHEnsoFREsIN ALCOHOLS AND METHOD I FOR. THEIR,PRODUCTION Edwin R. Littmann, Wilmington, Del., assignor to HerculesPowder Company, Wilmington,

, Del., a corporation of Delaware Application September 13,1935,

Serial No. 40,397

No Drawing.

10 Claims.

The term resin alcohol is descriptive of those formula AbCH2O--C'2I-I5is to react a resin 5 alcohols, usually primary alcohols, produced byalcohol of the general formula AbCH2-OH, in reduction of thehydro-aromatic acids occurring which Ab represents the hydrocarbonnucleus in natural resins. Thus, for example, rosin is of a resin acidwith diethyl sulfate in the prescomposed principally of thehydroaromatic acid, ence of an alkali metal hydroxide. The resin abieticacid, C19H29COOH, together with varying alcohol used need not be pureand, where a hyl0 amounts of its isomer, pimaric acid. Upon redrogenatedresin alcohol is used, the technical duction, by suitable methods, ofthese resin acids, product containing from 50 to 100% hydrothecorresponding resin alcohols may be obtained. genated resin alcohol maybe used directly, al- Thus, by the reduction of abietic acid, there willthough preferably the resin alcohol content be produced, depending uponthe particular should be 75% or over. The resin alcohol may 15 methodemployed, abietyl alcohol, C19I-I29CI-IzOI-I, be prepared from a refinedor unrefined resin or a hydrogenated abietyl alcohol as, for examacid,or if desired, may be prepared from a resin ple, dihydroabietyl alcohol,C19H31CH2OH, and acid which has been polymerized by suitable"tetrahydroabietyl alcohol, .CisHssCI-IzOH. Reduc-v treatment. v

20 tion of pimaric acid will produce in the same In forming an ether, inaccordance with this 2 way various pimaryl alcohols or hydrogenatedinvention, by reacting a mono or dialkyl sulfate pimaryl alcohols. witha resin alcohol several alternatives may be Abietyl alcohol may beproduced by there used. For example, one mole of hydrogenated duction of'abietic acidor, preferably, an abietic abietyl alcohol may be reactedwith one mole of acid ester, such as methyl abietate, by means of adialkyl s'ulfate, with or without the presence 25 sodium in alcoholicsolution in accordancewith of aninert solvent in the presence of onemole the method described by Ruzicka and Meyer, of an alkali, at atemperature-within the range Helv. Chim. Acta. 5, 581-93 (1932).Similarly, of about 10 C. to about 200 C. and with a rehydrogenatedabietyl alcohol may likewise be proaction period of from about 1 hour toabout 24- duced by treatment of-hydroabietic acid, orp'refhours.Solvents, such as,'for example,fbenzene, 30

erably its esters, in the same manner. Hydroxylene, decalin, gasoline,or the like, may, if deabietyl alcohol may likewise be produced "bysired, be used to lower the viscosity and increase catalytichydrogenation of abietyl alcohol pro-' the ease of reaction. Theprocedure may be duced in the manner described above. It is modified byusing 1 mole or more of a dialkyl more convenient, however, to producehydrosulfate per. mole of hydrogenated abietyl alcohol, 35 genatedabietyl alcohol by treatment of abietic' in the presence of aboutonemole of alkali inacid or its esters or hydrogenated abietic acid orderto increase the rate of reaction, the prodand its esters with hydrogenat relatively high ucts of which are the alkyl ether of hydrogenatedpressures and temperatures, and in the presence abietyl alcohol and thealkali salt of a mono- 40 of a catalyst such as a metal chromite.alkylsulfate. The time and temperature of heat- 40 It will be understoodthat the term hydroing are not critical and can be varied over asubgenated abietyl alcohol is used throughout this stantial range. Ithas, however, been found prefsp-ecification and in the claims to'indicate either erable to use a temperature within the range ofdihydroabietyl alcohol, tetrahydroabietyl alcohol, about 100 C. to about125 0., and a reaction or a mixture thereof. The product actuallyproperiod of about 7 to 8 hours. After the reaction 45 duced incommercial practice by any of the methhas been completed, the product isWashed with ods described above for the production of hydrowater untilneutral, dried and then distilled under genated abietyl alcohol is amixture of dihydroreduced pressure, in order to remove the solvents andtetra-hydroabietyl alcohols in varying proand unreacted alkyl sulfate.The ether, itself,

portions. may then be distilled under reduced pressurefor 50 Inaccordance with this invention, ethyl ethers further purification, ifdesired. The technical of resin alcohols, such as, for example, ethylethyl ether of hydrogenated abietyl alcohol, conethers of abietylalcohol, hydrogenated abietyl taining approximately 85% ether, will befound alcohol, pimaryl alcohol, hydrogenated pimaryl to boil at about185 C. to 205 C. at 2 mm. presalcohol of the general formulav sure.

It will be appreciated that the procedure and Ab CH2 O C2H5 conditionsof reaction described above are merely in which Ab stands for thehydrocarbon nucleus illustrative of a convenient method for the prepaofa resin acid, as for examplaabi-etic acid, or ration of these ethers andthat both the procedure 0 the isomeric pimaric acid, hydrogenatedabietic and, the conditions of reaction may be Varied This inventionrelates to ethyl ethers of resin alcohols, and more particularly to theethyl ethers of hydrogenated abietyl alcohol and to a method for theirproduction.

acid or the isomeric'hydrogenatcd pimaric acid are produced.

The procedure in accordance with this invention for the production ofethers of the general widely without affecting the operability of thereaction in question and without departing from the scope of thisinvention. For example, the inert solvent may or may not be used in thereaction, as desired, and when used may be added in widely varyingamounts. It will be appreciated that various inert solvents not namedabovecan be used in place of those named. While the'reaction willpreferably be carried out at a temperature within the range of about C.to about 150 C., the reaction temperature may be varied, if desired,within the range of about 0 C. to about 250 0., and it will beappreciated that these limits are not critical. The time of reactionwill be controlled largely by the temperature of reaction, and thereactivity of the reactants, and will usually be within the range ofabout 1 hour to about 24 hours.

The following example of the preparation of the ethyl ether ofhydrogenated abietyl alcohol will serve to illustrate the practicalprocedure in accordance with this invention:

A mixture of 25.4 grams (0.081 mole) of crude hydrogenated abietylalcohol (containing 93% alcohol), '27 grams (0.175 mole) of diethylsulfate (an excess), and 3.5 grams (0.087 mole) of sodium hydroxide, iswarmed in a steam bath with vigorous agitation for about 20 minutes. Thereaction begins with a pronounced increase in viscosity, so, soon afterthe beginning of the reaction cc. of benzene is added to reduce theviscosity, and hence allow efficient agitation. The reaction mixture isthen refluxed for about hour after separating solid material. 100 cc. ofa 5% solution of sodium hydroxide is then added to the re- .actionmixture, which is then heated for about 2 hours at the refluxtemperature to decompose the excess diethyl sulfate. The reactionmixture is then cooled, and the oil layer separated, washed with'wateruntil neutral, and dried. The solvent and unreacted diethyl sulfate arethen removed by distillation at reduced pressure. A cut boiling at about227 C. to 240 C. under a pressure of 15 mm. pressure is taken. A yieldof about 30 grams is obtained which gives an analysis of 1.8% ethoxyl,indicating a content of about 36% ethyl ether of hydrogenated abietylalcohol. The remainder of the product is unreacted hydrogenated abietylalcohol. This yield can be materiallyincreased by the use of a greaterexcess of diethyl sulfate, together with higher reaction temperaturesand longer heating periods.

The ethers of the resin alcohols in accordance with this invention arevaluable for use in the protective coating field, particularly asplasticizers for chlorinated rubber, nitro-cellulose, and celluloseacetate coating compositions.

It will be appreciated that the details and example hereinbefore setforth are illustrative only and are in no way in limitation of theinvention as herein broadly described and claimed.

What I claim and desire to protect by Letters Patent is:

1. A compound of the general formula where Ab stands for the hydrocarbonnucleus of a resin acid.

2. The ethyl ether of hydrogenated abietyl alcohol.

3. The method of preparing an ether which comprises reacting a compoundof the general formula Where Ab represents the hydrocarbon nucleus of aresin acid, with diethyl sulfate.

4. The method of preparing an ether which comprises reacting a compoundof the general formula where Ab stands for the hydrocarbon nucleus of aresin acid, with a material selected from the group consisting ofmonoalkyl sulfate and dialkyl sulfate.

10. The method of preparing an ether which comprises reactinghydrogenated abietyl alcohol with diethyl sulfate in the presence ofsodium hydroxide.

EDWIN R. LITTMANN.

